I have been conducting some research lately into DLP and employee theft. DLP is Data Loss Prevention or Data Leak Prevention depending on who you ask. Either way it means the same thing, information that leaves a business. During my research I started to notice a lot about companies online that was written by current or former employees. Sites like youropenbook.org allow searches inside of Facebook without being signed in or being someones "Friend". People are very open about what I consider confidential company information. Some people even go as far as discussing patients and breaking privilege.
Having proper policies in place to prevent employees from leaking any company, employee, or client information is the key to protecting privacy. Employees need to be educated on the risks associated with disclosing this information. If you have 50 or more employees consider bringing in an outside speaker that can be more direct with the risks and discuss what happens in other companies. No one can control what people say, but through education everyone will appreciate the risks.